The present invention relates to warehouse wagons and pertains particularly to reversible wagons having improved stability.
Small warehouse and yard wagons are extensively used around factories and warehouses for transporting materials and products between various storage and manufacturing areas and loading docks, and around airports for the handling of baggage and other cargo. Such wagons must be highly mobile, and must be small and maneuverable enough to move down narrow aisles and passageways. Such wagons must also be able to be formed in trains in order to have practical cargo-hauling capabilities. It is also desirable that such a wagon have a short turning radius in order to be maneuverable in and about confined areas and be reversible so that it can be used in areas where no turning space is available.
In order to be towable from either end, a wagon must have steerable wheels on both ends. Steerable wheels on both ends of a vehicle, however, generally make a vehicle very unstable so that control of the vehicle becomes a problem. Another desirable characteristic of such wagons is that they have good tracking ability, i.e. the ability to follow closely within the wheels of the towing vehicle. This is in order that a train of such vehicles can be formed in a train which can be taken around relatively short corners.
Still another desirable characteristic of such wagons is that they be able to go up and down ramps and still maintain load support on the wheels as well as stability.
Efforts to enhance one of the above desirable characteristics tend to aggravate another problem. For example, a short turning radius normally negates good tracking ability. Good turning radius by means of steering wheels also tends to negate stability.
Although prior efforts to achieve the above-desired characteristics have produced wagons having one or more of the above-desired characteristics, the prior art has failed to develop a wagon having all of the above-desired characteristics to an optimum degree.